The cognitive development from childhood to adolescence of low birthweight children born after medically assisted reproduction—a UK longitudinal cohort study

Abstract

Background Previous research has documented that children conceived through medically assisted reproduction (MAR) are at increased risk of poor birth outcomes, such as low birthweight (LBW), which are risk factors for stunted longer-term cognitive development. However, parents who undergo MAR to conceive have, on average, advantaged socioeconomic backgrounds which could compensate for the negative effects of being born LBW. Previous studies have not analysed whether the negative effects of LBW are attenuated among MAR conceived children. Methods We draw on the UK Millennium Cohort Study (sweeps 1–6) which contains a sub-sample of (N = 396) MAR-conceived children. The dependent variable measures cognitive ability at around ages 3, 5, 7, 11 and 14. We examine the cognitive development of four groups of children: MAR-conceived low birthweight (MAR LBW); MAR-conceived non-low birthweight (MAR NLBW); naturally conceived low birthweight (NC LBW); naturally conceived non-low birthweight (NC NLBW). We estimate the two following linear regression models for each sweep: (i) a baseline model to examine the unadjusted association between cognitive development and low birthweight by mode of conception; and (ii) a model adjusted by socio-demographic family characteristics. Results In baseline models, MAR LBW children [age 3: β = 0.021, 95% confidence interval (CI): -0.198, 0.241; age 5: β = 0.21, 95% CI: 0.009, 0.418; age 7: β = 0.163, 95% CI: -0.148, 0.474; age 11: β = 0.003, 95% CI: -0.318, 0.325; age 14: β = 0.156, 95% CI: -0.205, 0.517], on average perform similarly in cognitive ability relative to NC NLBW at all ages, and display higher cognitive scores than NC LBW children until age 7. When we account for family characteristics, differences are largely attenuated and become close to zero at age 14. Conclusions Despite the higher incidence of LBW among MAR compared with NC children, they do not seem to experience any disadvantage in their cognitive development compared with naturally conceived children. This finding is likely explained by the fact that, on average, MAR children are born to socioeconomically advantaged parents.

The Consequences of the COVID19 Pandemic for Fertility and Birth Outcomes: Evidence from Spanish Birth Registers

“…These patterns coincided eight-to-nine months after the sudden cease in activity of MAR centers in March 2020 (Vermeulen et al, 2020). MAR conceptions are more likely among highly educated older women, being the first child of a woman, and they more often result in multiple births (Cozzani, Aradhya, & Goisis, 2021;Goisis, Håberg, Hanevik, Magnus, & Kravdal, 2020), and are also more likely to result in children with poor health (Goisis et al, 2019).…”

The association between type of conception through medically assisted reproduction and childhood cognition: A Danish population-wide cohort study

“…Our study extends the literature on MAR conceived children's cognitive development by using population wide data from a context with high usage and easy availability of MAR treatment 30 and smaller variation in early life care and school quality than most other countries 31,32 , with previous work predominantly using data from settings with lower MAR uptake and more educational inequality, such as the UK 10,11 . By considering Denmark, where MAR conceived births now make up more than 8% of all birth, we have provided a vanguard view on the relationship between MAR conception and children's academic achievement.…”

“…The growth in MAR birth has motivated an expanding literature that considers the consequences of MAR conceptions for children's wellbeing and development. Children conceived through MAR have poorer birth outcomes 8,9 , but studies of later life wellbeing and cognitive ability generally find that association with cognitive ability is null or positive [10][11][12][13][14][15][16][17] . However, whereas studies using population wide data materials have been conducted for the association between MAR conception and birth outcomes 8,9 , the literature on cognitive ability and wellbeing has tended to be conducted on more selective cohort studies, which raises question of external validity of the findings 16 .…”

Well-being of children born after medically assisted reproduction

“…As further reassurance, a recent study by Cozzani et al [52] shows that despite the higher rates of adverse birth outcomes amongst MAR than naturally conceived children, the former do not experience any disadvantage in their cognitive development in childhood and adolescence. MAR-conceived children who are born low birth weight (LBW) do not show any disadvantage in cognitive development compared with naturally conceived children who are born normal weight.…”